Organic hydrogen peroxide addition compounds for vesicular image formation processes

ABSTRACT

Photographic images are produced by imagewise decomposition of addition compounds of hydrogen peroxide with organic compounds, the image being made visible, either physically by developing the gas bubbles formed during decomposition, or chemically by using the oxygen formed during decomposition for a color-forming reaction.

United States Patent 1191 Weyde et al.

ORGANIC HYDROGEN PEROXIDE ADDITION COMPOUNDS FOR VESICULAR IMAGE FORMATION PROCESSES Appl. No.: 198,947

Foreign Application Priority Data Nov. 17, 1970 Germany P 20 56 359.1

U.S. Cl. 96/50, 96/48 R Int. Cl G03c 5/26 Field of Search 96/55, 48, 60, 59,

[ 1 Oct. 16, 1973 [56] References Cited UNITED STATES PATENTS 3,674,490 7/1972 Matejec 96/48 R 2,346,090 4/1944 Staehle 96/48 R 3,615,491 10/1971 Weyde 96/50 Primary Examiner-Norman G. Torchin Assistant Examiner-Richard L. Schilling Attorney-Arthur G. Connolly et al.

[5 7 ABSTRACT Photographic images are produced by imagewise decomposition of addition compounds of hydrogen peroxide with organic compounds, the image being made visible, either physically by developing the gas bubbles formed during decomposition, or chemically by using the oxygen formed during decomposition for a colorforming reaction.

4 Claims, No Drawings ORGANIC HYDROGEN PEROXIDE ADDITION COMPOUNDS FOR VESICULAR IMAGE FORMATION PROCESSES This invention relates to a process for the production of photographic images by the imagewise decomposition of addition compounds of hydrogen peroxide with organic compounds, the image being made visible, either physically by developing the gas bubbles formed during decomposition, or chemically by using the oxygen formed during decomposition for a color-forming oxidation reaction.

The production of photographic images by the imagewise decomposition of compounds forming vesicles, especially of hydrogen peroxide, is known per se. U.S. Pat. No. 3,615,491 discloses a process for the production of photo-graphic images consisting of a silver image and a vesicular image superimposed upon the silver image. In this process, a silver image is initially produced in the usual way in a hydrophilic layer although it has far weaker density than conventional black-white images produced in that way. The layer is then brought into contact with hydrogen peroxide, which decomposes to form oxygen gas bubbles at those places at which the silver is present imagewise in finely divided form. Subsequent heating of the exposed material causes the vesicles to expand, resulting in the formation of a vesicular image (bubble image). Since the bubbles obtained scatter the light imagewise, these areas appear dark in transmitted light, but light when looked at in reflected light. Most of the incident light is let through at the unexposed areas of the layer. In this way, the silver image is intensified to a very considerable extent and, even with layers containing little silver, deep black high-contrast images are obtained. The quality of the photographic images obtained by this process is outstanding.

It is also known that the oxygen formed during the image-wise decomposition of hydrogen peroxide can be made visible chemically, by using it for a colorforming oxidation reaction, rather than physically by bubble formation as described above. In this process, a light-sensitive layer is exposed imagewise to form nuclei from noble metals of the Groups lb or VIII of the Periodic Table in imagewise arrangement, after which this layer is treated with peroxidic compounds which decompose catalytically at the nuclei formed in an imagewise arrangement, in the presence of reaction components for a color-forming oxidation reaction.

Instead of light-sensitive layers which, on exposure to light, form noble metal nuclei for the decomposition of hydrogen peroxide, it is also possible to use, for the aforementioned processes for the production of photographic images, layers containing substances which form catalase-active or peroxidase catalysts on exposure to light. Examples of suitable substances of this kind include certain complex compounds of heavy metals of the Groups VIb, VIIb or VIII of the Periodic Table of Elements with a monobasic or polybasic carboxylic acid. Compounds which give off iodine ions on exposure to light have a similar effect.

It is also possible to use, for the aforementioned processes, light-sensitive photographic materials which contain uniformly distributed catalase-active or peroxidase-active ferments such as catalase, peroxidase, haemoglobin or hemin, which are deactivated imagewise by exposure to actinic light. Positive images are directly obtained with materials of this kind.

Although the process referred to above give photographic images of high quality, they do have certain disadvantages especially when it comes to processing. These disadvantages result primarily from the difficulties involved in dosing hydrogen peroxide. In order to obtain a completely uniform treatment of each unit area of the exposed layer, the process has to be carried out very carefully, which makes automatic processing difficult.

It is among the object of the invention to simplify the photographic processes described above, especially in regard to the use of gaseous or dissolved hydrogen peroxide.

We now have found a process for the production of photographic images by the imagewise exposure of a photosensitive layer containing substances which, on exposure to light, form catalysts for the decomposition of hydrogen peroxide, followed by treatment of the exposed layer with a peroxidic compound to form a visible image, wherein an addition compound of hydrogen peroxide with an organic compound is used as peroxidic compound for treating the exposed layer.

The chemical nature of the organic addition component is not critical. The only requirements which the organic compound has to satisfy are that the addition compound with hydrogen peroxide should be sufficiently stable and should only be split at temperatures of from to 150C, preferably from to C, under the conditions of the process, accompanied by the liberation of H 0 Addition products of hydrogen peroxide with organic, preferably aliphatic, acid amides, for example with succinimide, asparagin or, in particular, urea, are particularly favourable. It is also possible, however, to use addition products with aliphatic polyhydric alcohols, preferably containing from three to six carbon atoms, for example with erythritol, mannitol or pinacol. Addition products of hydrogen peroxide with organic amines or acid hydrazides, for example addition products of H 0 with hexamethylene triamine, diacetyl hydrazine, succinic acid dihydrazine or malonic acid dihydrazide, can also be used.

Photosensitive layers which, on exposure to light, from imagewise noble nuclei which catalytically accelerate the decomposition of hydrogen peroxids, are preferred for carrying out the process according to the invention. It is preferred to use silver halide emulsion layers with a relatively low silver halide content, of the kind described in German Offenlegungsschrift'No.

It is also possible, however, to use the light-sensitive materials described above, containing substances which, on exposure to light, form catalase-active or peroxidase-active catalysts. Reference is made, for example, to U.S. Patent application Ser. No. 74,482- or U.S. Pat. No. 3,684,511, issued Aug. 15, 1972. The process according to the invention can also be carried out with the photosensitive materials described in U.S. Pat. No. 3,694,207, issued Sept. 26, 1972, which contain catalase-active or peroxidase-active ferments in uniform distribution in the light-sensitive layer which, on exposure to actinic light, are deactivated imagewise.

As already mentioned, it is preferred to use lightsensitive layers containing silver halides as the lightsensitive substances.

The process is particular advantageous since it is possible to start from silver salt and, more particularly, silver halide emulsion layers which have a relatively high sensitivity compared with conventional materials for the production of vesicular images.

in addition, it is possible to obtain a considerable indrease in the covering power of the silver images produced in the photographic silver salt layers by the superposition of the vesicular image. Accordingly, it is possible in the practical application of the process to start from layers that contain relatively little silver, and to convert the silver images produced therein, which have inadequate density, into images of normal density by superimposing the vesicular image or dye image. Images of adequate density are obtained simply by using light-sensitive silver salt emulsion layers, especially silver halide emulsion layers containing 0.2 g of silver per sq. metre. Apart from the fact that a considerable saving of silver results from this process, the combined silver vesicular images or silver dye images have the considerable advantage of extremely high definition.

It is also possible to obtain a relative increase in sensitivity. Image areas which in normal photographic processing by development remain hidden from the eye are rendered visible by the treatment with hydrogen peroxide, and subsequent bubble formation. Apparent increase in sensitivity of 5 DlN are obtained in this way. For example, a relatively non-sensitive finegrained photographic film with a silver halide emulsion layer which, in normal processing, has a sensitivity of l3DlN, can be exposed as if it had a sensitivity of approximately l8DlN without any evidence of loss in the image details, compared with an image obtained from the same photographic material by normal exposure and processing.

The addition compounds of H 0 with organic compounds used in accordance with the invention, especially the addition product of H 0 with urea, hereinafter referred to in short as carbamide perhydrate, can be used in a variety of different forms. The form in which they are used is governed primarily by the nature of the light-sensitive layer. Either the addition compound can be added to the light-sensitive layer itself during preparation, or alternatively it can be brought into contact with the light-sensitive layer, either before or after exposure. In the light-sensitive silver halide emulsion layers preferably used, the addition product of H 0 is brought into contact with the exposed and developed layer. Contacting can be carried out either by applying a paste containing the addition compound, or directly by applying a separate layer to the light-sensitive layer, in which case a sufficient quantity of the peroxidecontaining addition compound must be present in this separate layer. I

The concentration of the peroxide-containing addition compound in thelight-sensitive layer or separate layers can be varied within wide limits. The density of the image formed and the intensifying effect upon the silver image obtained by exposure and photographic development, if any, are governed to a'certain extent by the concentration of the peroxide in the layer. Quantities of the addition compound corresponding to a content of active hydrogen peroxide of from 0.01 to 10 g, preferably from 0.1 to 2 g per sq. metre of layer, have generally proved to be adequate.

Pastes containing the addition compound can be prepared according to the recipes normally used for producing processing pastes of this kind. For example, it is possible to use polyglycols, viscous or pasty organopolysiloxanes, waxes of widely differing chemical origin, fatty acids, amino fatty acids, fatty acid amides and fatty alcohols etc. To prepare the pastes, these sub stances are fused and the finely ground addition compound, for example the carbamide perhydrate, is added to the resulting melt. Naturally, the temperature should not be increased beyond the decomposition point of the addition compound. The pastes can be applied to the exposed light-sensitive layer or to a separate layer support, for example of paper or a cellulose ester. The layer is then brought into intimate contact with the light-sensitive layer containing the decomposition nuclei for H 0 and heated beyond the decomposition temperature of the addition compound. It is also possible, however, to arrange the layer with the addition compound at a certain distance, for example up to a few millimetres, from the exposed layer containing the decomposition nuclei, and subsequently to heat the two layers.

This may be accomplished by applying the layer containing the peroxide compound on to a permeable support such as a fleece or felt of glass or of a polymer for example a celluloseester e.g. celluloseacetate and to contact the photographic layer to be treated with the uncoated rear side of the material containing the peroxide layer.

In this case, only the hydrogen peroxide vapours formed during decomposition of the addition compound are acting on the light-sensitive layer.

In these embodiments it is advantageous to increase the amount of the peroxide compound in the layer. in most cases a concentration of at least 5 g of active hydrogen peroxide per square meter in the layer leads to satisfactory results. The layer may, however, contain far higher concentrations, for example up to 50 g per square meter. A higher amount and thicker layer is in particular desirable if the layer is to be used several times.

In any event, the process according to the invention comprises the steps of exposing the light-sensitive layer and, optionally, a further process step for producing the decomposition nuclei for the hydrogen peroxide, for example in the form of a photographic development for forming silver nuclei. This is followed by heating in the presence of the peroxide addition compound, as a result of which hydrogen peroxide is liberated. The hydrogen peroxide is decomposed on the catalytically active decomposition nuclei. The image is made visible as mentioned above, either physically by bubble formation, or chemically by the presence of reaction components for a color-forming oxidation reaction. Fuller details in this respect can be found in the aforementioned Patent Specifications. l

The present invention obviates the disadvantages attending known processes using dissolved or gaseous hydrogen peroxide. The small quantities of hydrogen peroxide required for photographic processes of this kind which have to be present briefly in high concentrations are formed in a uniform and highly reproducible manner during decomposition of the peroxide addition compound. As a result, highly uniform photographic images of high coverage are obtained.

The decomposition temperature of the peroxidecontaining addition compounds can be varied within certain limits by the addition of certain compounds which influence the stability of the addition compounds. Examples of additives such as these include small quantities of acid-reacting substances such as oxalic acid, citric acid, salicylic acid, tannin, boric acid, sodium bisulfate or acid sodium phosphate. In general, the stability of the addition compounds can be improved by the addition of substances such as these.

When the image is made visible physically by bubbles, these bubbles are formed in the same temperature range as that in which the addition compound of the hydrogen peroxide decomposes. In this connection, it is of advantage to subject the light-sensitive layer containing the decomposition nuclei for hydrogen peroxide, for example the developed silver halide emulsion layer, briefly, i.e. for l to 5 seconds, to an atmosphere of water vapour at 50 to 90C either during or after the heating in the presence of the addition compound.

Making the image visible by decomposing the peroxide can be carried out either physically or chemically. Thus, the developed oxygen can be made visible in the form of a vesicular image for example by the process described in the aforementioned U.S. Pat. No. 3,615,491. It is also possible to decompose the peroxide compounds in the presence of reaction components for a color-forming oxidation reaction. Processes of this kind are described in U.S. Pat. No. 3,674,490,issued July 4, 1972.

The layers according to the invention contain the light-sensitive substances, preferably in dispersion in a binder. Examples of suitable binders include silica gel, polyvinyl acetate, partially hydrolyzed polyvinyl acetate, polyvinyl alcohol, cellulose esters such as cellulose acetate or cellulose butyrate, carboxymethyl cellulose or natural binders, especially proteins such as gelatin.

In this way, bubble formation, which takes place only very slowly when the treatment is carried out with hydrogen peroxide alone, occurs very quickly. It has proved to be even more favourable to expose the layer to an alkaline atmosphere of water vapour, pH values of from 8 to 12 being suitable. This can readily be achieved by adding small quantities of ammonia or vapours of volatile amines to the water vapour. The concentration of the alkaline additives is by no means critical. Quantities of from 0.1 to 5 by volume, preferably from 0.3 to l by volume, have generally proved to be adequate.

The visible image can also be produced chemically by carrying out heating of the exposed layer with the addition compound in the presence of reaction components for a color-forming oxidation reaction. Suitable processes are described in the aforementioned U.S. Pat. No. 3,674,490, issued July 4, 1972.

The peroxide-initiated dye formation also takes place more quickly when the layer has been subjected to a brief treatment with water vapour after exposure.

Reaction components of the kind which give extremely deep-colored compounds during oxidation with the catalytically activated peroxide compound, are of course preferred for the oxidative dye-forming reaction.

The reaction components can be organic compounds which themselves yield the image dye during oxidation, for example amino-, hydroxyor aminohydroxy compounds of isocyclic or heterocyclic aromatic compounds.

The following are mentioned by way of example: phenol, aniline, pyrocatechol, resorcinol, hydroquinone, o-, mand p-phenylene diamine, N,N-dimethylphenylene diamine, N,N-diethyl-phenylene diamine, N,N-ethylmethyl phenylene diamine, o-, mand pamino phenol, p-methylaminophenol, 2,4-diamino-lphenol, 1,7-dihydroxy naphthalene, 2,3-dihydroxy napthalene, 1,6,7-trihydroxy naphthalene, 1,2-diamino naphthalene, 1,8-diamino naphthalene, benzidine, 2,2'-diamino diphenyl, 8-hydroxy quinoline, S-hydroxy quinoline, 2-hydroxy carbazole and l-phenyl-3- pyrazolone.

The amino-, hydroxyor aminohydroxy compounds can also be substituted, for example by halogen, alkyl, aryl, alkoxy, sulfonic acid, nitro, keto, carboxylic acid or carbonamide groups. The following are mentioned by way of example: 2,5-dichloro-p-phenylene diamine, guaiacol, 4-methoxy-l-naphthol, l-hydroxy-Z-amino- 4-benzene sulfonic acid, 1-amin0-2-hydroxy-4-benzene sulfonic acid, 3-amino-5-sulfo-salicyclic acid, 1,6,7- trihydroxy naphthalene-3-sulfonic acid, benzidine-2,2'- disulfonic acid, benzidine-3,3'-disulfonic acid, 1,8- dihydroxy naphthalene-3,6-disulfonic acid and 4- nitropyro-catechol. 1

In some instances, mixtures of several of these compounds actually show much stronger dye formation than the individual components during oxidation. For example, a mixture of o-phenylene diamine and pyrocatechol promotes greater dye formation. Even components which, in their own, do not give any dyes during oxidation, for example tetrabromo-hydroquinone or tetrabromo-pyrocatechol, can intensify dye formation when added to other hydroxy-, aminoor aminohydroxy compounds.

Monomeric or polymeric dyes related to the quinone imines and azines are formed during oxidation of the aromatic amino-, hydroxyand/or aminohydroxy compounds. A few examples of this oxidative dye formation are described in HR. SCHWEIZER Kuenstliche organische Farbstoffe und ihre Zwischenprodukte", Springer-Verlag, Berlin-Gottingen-I-Ieidelberg (1964), pages 222, 275, 281 and 293; NJ. WOROSHOW Grundlagen der Synthese von Zwischenprodukten und Farbstoffen, Akademie-Verlag, Berlin (1966), pages 703 789; A. SCHAEFFER Chemie der Farbstoffe und deren Anwendung (Technische Fortschrittsberichte, Band 60), Theodor-Steinkopff-Verlag, Dresden-Leipzig (1963), pages'59 et seq. I

In addition to dye intermediate products, it is of course also possible to use leuco dye compounds and vat dyes which can be oxidized into dyestuffs. For examples of these dyes, see I-l.R. SCI-IWEIZER Kuenstliche organische Farbstoffe und Zwischenprodukte, Springer-Verlag, Berlin-Gottingen-l-leidelberg, (1964) pages 250 and 320. s

Oxidizable organic compounds which only give the image dye in a subsequent reaction with other compounds, are also suitable for the process according to the invention. In principle, it is possible to use any reaction system which undergoes oxidative coupling to form dyes. Reference is made in particular to the socalled color-forming photographic developers of the phenylene diamine or aminopyrazolone series (cf. for example, C.E.K. MEES and TH. JAMES The Theory of the Photographic Process", 3rd Edition, MacMillian Co. New York (1966), page 382; and H.R. SCHWE- IZER Kuenstliche organische Farbstoffe und ihre Zwischenprodukte, Springer-Verlag, Berlin- Goettingn-Heidelberg, (1964), page 295). lsocyclic and heterocyclic hydrazines can also be oxidatively coupled with suitable components to form dyes (cf. for example H. HUNIG et al., Angew. Chem. 74 1958 215; S. HUNIG, Chimia (1961), 133 and Angew. Chem. 74 (1962) 818). The color-forming photographic developer substances are catalytically oxidized by the peroxide compounds on the catalyst distributed imagewise. Their oxidation products can then react with photographic color couplers known per se, whiqh are also present, to form dyes. Any color couplers can be used for this purpose, for example those of the phenol or naphthol series as blue-green couplers, those of the indazole series as purple couplers, and those auf the benzoyl acetanilide series as yellow couplers.

EXAMPLE 1 A photographic material with a silver bromide emulsion layer on a cellulose acetate support which contains 3.5 mol of silver iodide, based on the silver halide, whose silver covering amounts to 0.2 g of silver per sq. metre, is exposed to form an image. This is followed by development in a developer of the following composition:

hydroquinone p-methyl aminophenol sodium sulfite sodium carbonate water to l litre The material is then fixed in the usual way with an aqueous sodium thiosulfate bath and dried.

A negative image of the original is obtained; it is only of low density and cannot be copied by conventional methods.

To intensify the image, it is coated with a peroxide paste of the following composition (in a layer thickness of from 0.2 to 3 pm):

15.0 g of percarbamide (1:1 addition product of H 0 with urea) 85.0 g of polyethylene glycol (molecular weight 8000). This is followed by heating for seconds at 90C as a result of which the peroxide compound decomposes on the image silver and a vesicular image is formed.

The pastes are prepared by fusing the polyglycols at temperatures below the decomposition point of the peroxide compound, adding the very finely powdered organic peroxide and grinding to form a homogeneous suspension. For application to the film, this suspension is fused at the lowest possible temperature.

Instead of the aforementioned polyethylene glycol,it is also possible to use one with a different molecular weight. Polyethylene glycols with a molecular weight of from 6000 to 12.000 have proved to be the most suitable. To lower the melting point, it is also possible to use mixtures of polyethylene glycols with one another or with other compounds, for example mixtures with alcohols, in particular lower aliphatic alcohols, polyglycol ethers or alkyl polyglycol ethers, fatty alcohols, or methylene glycols. In this instance, the polyethylene glycol can also be replaced by the aforementioned substances. To improve the spreading properties of the pastes, it can occasionally be of advantage to use mixtures of filmforming agents or to add wetting agents to the pastes.

It can also be of advantage, in order to improve the stability of the vesicular image, to add substances which promote strong adhesion between the layer of paste and the gelatin layer containing the vesicular image. Examples of substances such as these include carnauba wax, polyester waxes, stearyl amide or amino fatty acids.

EXAMPLE 2 Perparation of the light-sensitive material: 20 g of green ammonium ferricitrate are dissolved in 80 cc of water 6 g of ammonium ferrioxalate are dissolved in 60 cc of water 5 g of K Fe(CN) are dissolved in 50 cc of water 1 g of citric acid is dissolved in 10 cc of water 12 g of gelatin are dissolved in 200 cc of water.

The above solutions are mixed together in red dark room light, and the mixture is cast on to a layer support of cellulose triacetate. The dried layer has a thickness of approximately 10 am. Processing:

The dried layer is exposed behind a grey step wedge in a conventional Sensitometer (exposure time 10 seconds with a 100 Watt lamp). The layer is then exposed for about 1 minute to an atmosphere of water vapour at about C. It is then rinsed with water for 10 minutes, after which it can be exposed to daylight. A virtually invisible blue image of the original is obtained from this treatment.

The image is coated with a peroxide paste as described in Example 1, followed by further processing as described in that Example.

EXAMPLE 3 A substantially fog-free silver bromide iodide gelatin emulsion layer (4.5 mol of silver) is cast on to a polyethylene terephthalate substrate. Layer thickness about 10 a. After image-wise exposure (0.5 seconds with X- rays between fluorescence-intensifying films), the layer is initially treated for 5 minutes at 20C in the following developer:

3.5 g of p-methylaminophenol 9.0 g of hydroquinone 60.0 g of Na,so, sicc. and

40.0 g of Na CO in 1 litre of water After brief intermediate rinsing with water for 5 minutes, the layer is fixed with a bath of the following composition: I

250.0 g of Na s o,.5ii,0 and 20.0 g of NaHSO in 1 litre of water.

It is then coated with the paste described in Example 1 and heated at C.

The layer is then treated for 2 minutes with a bath of the following composition:

20 g of N,N-diethyl-p-phenylene diamine sulfate 20 g of pyrocatechol and 10 g of sodium sulfite 'sicc. made up to 1 litre with water and adjusted to pH 8 with Na CO A deep-colored dye image is formed after 10 to 15 seconds.

EXAMPLE 4 A mixture of ml of a highly sensitive AgBremulsion and 500 ml of a 10 by weight aqueous solu tion of the cyan color coupler CO-NH-CIBHU I S H are cast to form an approcimately 10 thick layer. Silver covering approximately 0.5 g of AgNO per square metre. An approximately 5 1. thick gelatin protective layer is then cast over this layer.

After the layer has been dried, it is exposed imagewise behind a grey step wedge and then developed in a developer of the following composition:

5 g of p-methyleminophenol 6 g of hydroquinone 40 g of Na SO sicc.

water to 1 litre adjusted to pH 10.5 with K CO The layer is then coated with one of the peroxide pastes described in Example 1 and heated to a temperature of 80C. This is followed by spraying with a solution of the following composition:

20 g of 2-amino-5-(N-ethyl-N-oxoethyl)- aminotoluene 10 g of sodium sulfite sicc.

water to 1 litre adjusted to pH 8 with Na CO A cyan dye image is formed.

If other color couplers are used instead of the aforementioned color coupler from the naphthol series, it is possible to obtain differently colored images. Thus, couplers of the indazole or pyrazolone series can be used as magenta couplers, and those of the ben zoylacetanilide series as yellow couplers.

We claim:

1. In the process for the production of photographic images including the steps of imagewise exposing a light sensitive layer containing substances which on exposure form catalysts for the decomposition of hydrogen peroxide; developing the exposed layer to form an image material therein; treating the said layer containing said image material with a peroxide compound capable of forming with said image material a visible product; and heating said layer; the improvement according to which the peroxide is an addition compound of hydrogen peroxide that liberates hydrogen peroxide.

2. The process of claim 1, wherein an addition compound with hydrogen peroxide has a decomposing temperature between 60 and C.

3. The process of claim 2, wherein the hydrogen peroxide forming compound is an addition compound of hydrogen peroxide with an aliphatic acid amide, aliphatic polyhydric alcohol, aliphatic amine or acylsubstituted hydrazine.

4. The process of claim 3, wherein the hydrogen peroxide forming compound is an addition product of hy drogen peroxide with urea. 

2. The process of claim 1, wherein an addition compound with hydrogen peroxide has a decomposing temperature between 60* and 150*C.
 3. The process of claim 2, wherein the hydrogen peroxide forming compound is an addition compound of hydrogen peroxide with an aliphatic acid amide, aliphatic polyhydric alcohol, aliphatic amine or acyl-substituted hydrazine.
 4. The process of claim 3, wherein the hydrogen peroxide forming compound is an addition product of hydrogen peroxide with urea. 